1. Field of the Invention
The present invention relates to a boom assembly of an operating machine such as a front loader.
2. Description of the Related Art
A boom assembly of a front loader includes a boom assembly formed by joining a front boom sub assembly on the front of the center in a longitudinal direction of the boom assembly, and a rear boom sub assembly on the rear of the center in the longitudinal direction of the boom assembly (for example, see Japanese Patent Application “kokai” No. 11-158907).
A boom assembly of a front loader also includes a round boom assembly bent at the center in a longitudinal direction so as to form a round shape protruding upward when seen from the side (for example, see Japanese Patent Application “kokai” No. 11-158907 and Japanese Patent Application “kokai” No. 6-313325).
A boom assembly of a front loader further includes a boom assembly in which a body portion is formed into an angle protruding upward when seen from the side by bending a flat sheet material into a Π-shape in section opening downward and then further bending the flat sheet material at the center in a longitudinal direction of the boom assembly (for example, see Japanese Patent Publication No. 7-108410).